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Adaptively robust filtering with classified adaptive factors

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Progress in Natural Science:Materials International 2006年第8期16卷 846-851页

作者： CUI xianqiang and YANG Yuanxi (xi’an Research Institute of surveying and mapping, xi’an 710054, china) xi'an Research Institute of surveying and mapping Xi'an 710054 China

The key problems in applying the adaptively robust filtering to navigation are to establish an equivalent weight matrix for the measurements and a suitable adaptive factor for balancing the contributions of the measurements and the predicted state information to the state parameter estimates. In this paper, an adaptively robust filtering with classified adaptive factors was proposed, based on the principles of the adaptively robust filtering and bi-factor robust estimation for correlated observations. According to the constant velocity model of Kalman filtering, the state parameter vector was divided into two groups, namely position and velocity. The estimator of the adaptively robust filtering with classified adaptive factors was derived, and the calculation expressions of the classified adaptive factors were presented. Test results show that the adaptively robust filtering with classified adaptive factors is not only robust in controlling the measurement outliers and the kinematic state disturbing but also reasonable in balancing the contributions of the predicted position and velocity, respectively, and its filtering accuracy is superior to the adaptively robust filter with single adaptive factor based on the discrepancy of the predicted position or the predicted velocity.

关键词： Kalman filtering adaptive filtering robust estimation adaptive factor.

A new learning statistic for adaptive filter based on predicted residuals

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Progress in Natural Science:Materials International 2006年第8期16卷 833-837页

作者： YANG Yuanxi and GAO Weiguang (xi'an Research Institute of surveying and mapping, xi'an710054, china Institute of surveying and mapping, University of Information Engineering, Zhengzhou 450052, china) xi'an Research Institute of surveying and mapping Xi'an 710054 China Institute of surveying and mapping University of Information Engineering Zhengzhou 450052 China

A key problem for an adaptive filter is to establish a suitable adaptive factor for balancing the contributions of the measurements and the predicted state information from some kinematic models. The reasonable adaptive factor needs a reliable learning statistics to judge the state kinematic model errors. After analyzing the existing two kinds of learning statistics based on the state discrepancy and variance component ratio, a new learning statistic based on predicted residuals is set up, which is different from the exiting learning statistics. The new learning statistic does not need to estimate the kinemetic state parameters before the filtering process, Of course, it does not need necessary measurements to estimate state parameters for all observation epochs. The new learning statistic can be applied together with the learning factor constructed by the state discrepancy. The advantages and shortcomings of the new learning factor are analyzed, and an example is given.

关键词： adaptive factor adaptive filter kinematic model predicted residual.

Combined adjustment project of national astronomical geodetic networks and 2000' national GPS control network

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Progress in Natural Science:Materials International 2005年第5期15卷 435-441页

作者： YANG Yuanxi1*, ZHA Ming2, SONG Lijie3, WEI Ziqing1, WANG Zhouping2, OUYANG Guichong2, XU Bilin2, WU xiaoping3 and WANG Junqin4(1. xi'an Research Institute of surveying and mapping, xi'an 710054, china 2. xi'an Informational and Technical Center of surveying and mapping, xi'an 710054, china 3. Zhengzhou Institute of surveying and mapping, Zhengzhou 450052, china 4. The First surveying Team of Tianjin, Tianjin 300140, china) xi'an Res. Inst. of surveying and mapping Xi'an 710054 China xi'an Info. and Technical Ctr. of surveying and mapping Xi'an 710054 China Zhengzhou Inst. of surveying and mapping Zhengzhou 450052 China First surveying Team of Tianjin Tianjin 300140 China

The combined adjustment project of the nationwide astronomical geodetic networks and 2000' national GPS control network involve 48519 terrestrial observational stations and 2666 GPS observational stations. In the terrestrial network, 25107 stations are height fixed and 23412 stations are in three dimensions. 440793 terrestrial observations and 183668 unknowns are involved in the adjustment. The three-dimensional observational models for the adjustment have been established. The crustal deformation influences and corrections are researched. Fast methods of solving partitioned adjustment for super large-scale geodetic network have been studied. The standard deviations of three-dimensional coordinates for all stations are evaluated. As a result of the combined adjustment, a unified national geodetic network with nearly 50000 stations is established, the high accurate three-dimensional geocentric coordinates are obtained. The standard deviation for geoid is averagely 0.2 m, for vertical deflection is about 1.5″, for the horizontal position is about 0.12 m, for the geodetic height is about 0.14 m, and for the three-dimensional position is averagely 0.3 m.

关键词： astronomical geodetic network GPS network combined adjustment datum geocentric coordinates.

General inverse of Stokes, Vening-Meinesz and Molodensky formulae

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Science china Earth Sciences 2006年第5期49卷 499-504页

作者： CHENG Luying1,2 & XU Houze1 1. Institute of Geodesy and Geophysics, Chinese Academy of Sciences, Wuhan 430077, china 2. xi’an Research Institute of surveying and mapping, xi’an 710054, china Institute of Geodesy and Geophysics Chinese Academy of Sciences Wuhan China xi’an Research Institute of surveying and mapping Xi’an China

The operator operations between the disturbing potential and the geoidal undulation, the gravity anomaly, the deflection of the vertical are defined based on the relations among the gravity potential, the normal gravity potential and the disturbing potential. With the sphere as the boundary surface, based on the solution of the external boundary value problem for the disturbing potential by the spherical harmonics in the physical geodesy, the general inverse Stokes’ formula, the general inverse Vening-Meinesz formula and the general Molodensky’s formula are derived from the operator operations defined. The general formulae can get rid of the restriction of the classical formulae only used on the geoid. If the boundary surface is defined as the geoid, the general formulas are degen- erated into the classic ones.

关键词： spherical harmonics, boundary value problem, general inverse Stokes' formula, general inverse Vening-Meinesz formula, general Molodensky's formula.

Synthetically adaptive robust filtering for satellite orbit determination

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Science china Earth Sciences 2004年第7期47卷 585-592页

作者： YANG Yuanxi1 & WEN Yuanlan2 1. xi’an Research Institute of surveying and mapping, xi抋’an 710054, china 2. College of Aerospace and Material Engineering, National University of Defense Technology, Changsha 410073, china xi’an Research Institute of surveying and mapping Xi’an China College of Aerospace and Material Engineering National University of Defense Technology Changsha China

The quality of the satellite orbit determination is rested on the knowledge of per-turbing forces acting on the satellite and stochastic properties of the observations, and the ability of controlling various kinds of errors. After a brief discussion on the dynamic and geometric orbit determinations, Sage adaptive filtering and robust filtering are reviewed. A new synthetically adaptive robust filtering based on a combination of robust filtering and Sage filtering is *** is shown, by derivations and calculations, that the synthetically adaptive robust filtering for orbit determination is not only robust but also simple in calculation. It controls the effects of the outliers of tracking observations and the satellite dynamical disturbance on the parameter esti-mates of the satellite orbit.

关键词： satellite orbit, Sage filtering, adaptive orbit determination, robust estimation.

National 2000' GPS control network of china

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Progress in Natural Science:Materials International 2007年第8期17卷 983-987页

作者： Yang Yuanxi~(1**) Tang Yingzhe~1 Chen Chuanlu~2 Wang Min~3 Zhang Peng~4 Wang xiaorui~2 Song Lijie~5 Zhang Zusheng~6 (1.xi'an Research Institute of surveying and mapping,xi'an 710054,china 2.Geodetic Data Processing Center,xi'an 710054,china 3.Center of Earthquake Analysis and Prediction,china Seismological bureau,Beijing 100036,china 4.National Geomatics Center of china,Beijing 100044,china 5.Institute of surveying and mapping,Zhengzhou University of Information Engineering,Zhengzhou 450052,china 6.First Crustal Deformation Monitoring Center,china Seismological bureau,Tianjin 300180,china) xi'an Research Institute of surveying and mapping Xi'an 710054 China Geodetic Data Processing Center Xi'an 710054 China Center of Earthquake Analysis and Prediction China Seismological Bureau Beijing 100036 China National Geomatics Center of china Beijing 100044 China Institute of surveying and mapping Zhengzhou University of Information Engineering Zhengzhou 450052 China First Crustal Deformation Monitoring Center China Seismological Bureau Tianjin 300180 China

An accurately unified national GPS network with more than 2500 stations,named"National 2000' GPS Control Net- work",signed the epoch 2000.0,has been established by integrating the existing six nationwide GPS networks of china set up by differ- ent departments with different *** paper presents the characteristics of the existing GPS networks,summarizes the strategies in the integrated adjustment of the GPS network,including functional model,stochastic model as well as the adjustment principle modifi- *** modifying the adjustment strategies according to the characteristics of the existing GPS networks and under the support of the IGS stations,the accuracy of the integrated national GPS network is greatly *** datum differences among the sub networks disappear,the systematic error influences are weakened,and the effects of the outliers on the estimated coordinates and their variances are *** is shown that the average standard deviation for the horizontal component is smaller than 1.0 cm,the vertical component is smaller than 2.0 cm,and the three-dimensional (3-D) position of geocenter coordinates is smaller than 3.0 *** exterior checking ac- curacy for the 3-D position is averagely better than 1.0 cm.

关键词： GPS control network adjustment systematic errors robust estimation variance component estimation coordinate system

Digital close-range photogrammetric application to small-scale physical simulation experiment

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中国有色金属学会会刊：英文版 2011年第S3期21卷 681-685页

作者： LI Chun-yi1, CUI xi-min2, YU Yi-ju3 1. School of surveying and Landing Information Engineering, Henan Polytechnic University, Jiaozuo 454003, china 2. College of Geoscience and surveying Engineering, china University of Mining and Technology, Beijing 100083, china 3. surveying and mapping Press, Beijing 100045, china School of surveying and Landing Information Engineering Henan Polytechnic University Jiaozuo 454003 China College of Geoscience and surveying Engineering China University of Mining and Technology Beijing 100083 China surveying and mapping Press Beijing 100045 China

In order to research the possibility of digital close-range photogrammetric surveying in small scale physical simulation experiment, physical model coinciding with engineering practice was constructed based on similar theory. The datum processing method and surveying precision of digital close-range photogrammetric were analyzed. And the function relationship between overburden subsidence factor qr and the ratio z/H of stratum horizon z and mining depth H was researched. The results show that surveying points position mean error along horizontal direction is ±0.131 mm and vertical direction is ±0.192 mm. Therefore, multi-taking station cross direction digital close-range photogrammetric can completely satisfy the precision need of physical simulation experiment. And the empirical formula can be utilized to represent evolution law of stratum subsidence factor.

关键词： close-range photogrammetric physical simulation light-rays adjustment surveying precision subsidence factor

Mine laneway 3D reconstruction based on photogrammetry

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中国有色金属学会会刊：英文版 2011年第S3期21卷 686-691页

作者： ZHANG Chun-sen College of Geomatics, xi’an University of Science and Technology, xi’an 710054, china College of Geomatics Xi'an University of Science and Technology Xi'an 710054 China

Aiming at the problem of 3D reconstruction for mine laneway, the technique route and step were given based on digital close range photogrammetry and traverse surveying. 3D coordinates of laneway traverse point, photogrammetric station, control strip points were obtained by electronic total station based on mine coordinate system. The feature points were extracted from the scene images. The camera was calibrated by direct linear transformation (DLT). 3D relative coordinates of the arbitrary feature points in mine laneway were calculated after feature points being matched, in which the origin of coordinate system is photogrammetric station. The 3D absolute coordinates of the feature points in mine laneway can be obtained by the combined adjustment of photogrammetry and non-photogrammetric observations and coordinate conversion. The measurable 3D model of the underground laneway terrain surface was constructed with the 3D coordinates of feature points on the image pairs obtained. The measurable 3D model of a corridor was reconstructed by the mentioned method and the experiment precision with an average standard deviation of 0.013 6 m between the 3D model and practical measure was obtained by electronic total station. The experimental resulted show the validity of the proposed approach.

关键词： digital mine mine laneway photogrammetry 3D reconstruction direct linear transformation (DLT)

Vision navigation algorithm for mine agent based on quaternion

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中国有色金属学会会刊：英文版 2011年第S3期21卷 610-615页

作者： LI Ke-zhao1, 4, LEI Wei-wei1, 2, GUO Zeng-zhang1, 2, WU Li-xin3, ZHANG Qin4 1. School of Survey and Land Information Engineering, Henan Polytechnic University, Jiaozuo 454003, china 2. Key Laboratory of Mine Spatial Information Technologies of State bureau of surveying and mapping, Henan Polytechnic University, Jiaozuo 454003, china 3. College of Resources and Civil Engineering, Northeastern University, Shenyang 110819, china 4. College of Geology Engineering and Geomatics, Chang’an University, xi’an 710054, china School of Survey and Land Information Engineering Henan Polytechnic University Jiaozuo 454003 China College of Geology Engineering and Geomatics Chang'an University Xi'an 710054 China Key Laboratory of Mine Spatial Information Technologies of State bureau of surveying and mapping Henan Polytechnic University Jiaozuo 454003 China College of Resources and Civil Engineering Northeastern University Shenyang 110819 China

Autonomous relative navigation is the key technology in mining or rescuing. On the basis of mine requirement and the theories of machine vision, an autonomous relative navigation algorithm for mine agent based on quaternion was proposed. In rotation transformation, this algorithm was represented by using quaternion. Because the Jacobi matrix of this method is lower than that of Hall algorithm, the calculation efficiency is improved by using this algorithm. The results of these experiments show that the computation burden of this algorithm based on quaternion is about half that of Hall algorithm. This algorithm based on quaternion is improved as a valid way to solve the problem of mine real-time navigation.

关键词： quaternion mine agent vision navigation